Method for making composite centrifugally cast furnace roll rings for furnace rolls

Abstract

A method for making either a ringless annealing furnace roll or a furnace roll having a series of spaced rings for supporting a metal strip being removed from an annealing furnace. Each ring is centrifugally cast with an outer rim of a steel alloy that is relatively insoluble with respect to the alloy of the strip being transferred from the furnace, and an inner liner of an alloy that can be readily welded to a roll. The inner liner material is fused to the rim material to form a composite ring.

Having described my invention, I claim: 
     
       1. A method for making a roll for transferring a flat, heated strip of a first steel alloy from a furnace, said roll comprising an elongated tubular body having a longitudinal axis, the body being formed of a second steel alloy, a support layer carried on said tubular body forming a surface for contacting and supporting the flat heated strip on the tubular body as the tubular body is being rotated, said support layer having an outer strip-contacting surface of a third steel alloy that is relatively insoluble with respect to the first steel alloy of the heated strip; said method comprising the steps of: centrifugally casting the support layer of said third steel alloy, and then centrifugally casting the tubular body to the support layer while the support layer is sufficiently heated to form a fused connection therebetween.   
     
     
       2. A method for making a ring for a roll used for transferring a flat, heated strip of a first steel alloy from an annealing furnace, the ring having an outer strip-contacting rim, the roll being formed of a second steel alloy, said method comprising the steps of selecting a third steel alloy for the outer rim of the ring that is relatively insoluble in the first steel alloy of the strip material, casting the outer ring, selecting a fourth steel alloy for the inner liner of the ring that can be welded to the roll, and then fusing the liner to the inside of the outer rim. 
     
     
       3. A method as defined in claim 2, in which the fusing step comprises centrifugally casting a heated rim, and then centrifugally casting a liner to the inside of the rim while the rim is sufficiently hot to form a fused alloy between the rim and the liner. 
     
     
       4. A method as defined in claim 2, including the step of centrifugally casting a tubular body of the third steel alloy, fusing a liner of the fourth steel alloy to the inside of the tubular body, and then dividing the fused body and liner into a plurality of rings. 
     
     
       5. A method for making a roll for transferring a flat, heated strip of a first steel alloy from a furnace, said roll comprising an elongated tubular body having a longitudinal axis, the body being formed of a second steel alloy, shaft means attached to opposite ends of the body for supporting the body for rotation about an axis; support structure carried on said tubular body forming a discontinuous surface for contacting and supporting the flat heated strip on the tubular body as the tubular body is being rotated; said support structure having an outer strip-contacting layer of a third steel alloy that is relatively insoluble with respect to the first steel alloy of the heated strip; and an inner layer of a fourth steel alloy that is relatively soluble with the second steel alloy of the tubular body, the inner layer being heat fused to the outer layer; said method comprising the steps of: centrifugally casting the outer layer of said third steel alloy, and then centrifugally casting the inner layer to the outer layer while the outer layer is sufficiently heated to form a fused connection therebetween.   
     
     
       6. A method as defined in claim 5, in which the support structure comprises a plurality of rings connected to and spaced along the tubular body. 
     
     
       7. A method for making a ring for a roll used for transferring a flat, heated strip of a first steel alloy from an annealing furnace, the ring having an outer strip-contacting rim, and an inner liner, the roll being formed of a second steel alloy, said method comprising the steps of: selecting a third steel alloy for the outer rim of the ring that is relatively insoluble in the first steel alloy of the strip material;   selecting a fourth steel alloy for the inner liner of the ring that can be welded to the roll, and then   fusing the liner to the inside of the outer rim.   
     
     
       8. A method as defined in claim 7, in which the fusing step comprises centrifugally casting a heated rim, and then centrifugally casting a liner to the inside of the heated rim while the rim is sufficiently hot to form a fused alloy between the rim and the liner. 
     
     
       9. A method as defined in claim 7, including the step of centrifugally casting a tubular body of the third steel alloy, fusing a liner of the fourth steel alloy to the inside of the tubular body, and then dividing the fused body and the liner into a plurality of rings.